Ok, so I took DS to a local store and sat him in both a Radian80 and a Marathon. They didn't have the Radian65. The Radian has crazy high top slots and seat back compared to his Touriva! The Marathon had top slots that looked about an inch lower, but the seat back was much shorter. On the shelf, side by side, they looked the same height, but the Radian's seat is so super low, that it gave a LOT more height room.
I think I am pretty well sold on the Radian now, but now I am wondering what the difference is between the 65 and the 80? Is it only weight? Or is it slot height as well? If it is weight alone, I think the 65 should be fine, as DS only weighs 24 pounds, and has been a sting bean since day one. I highly doubt he will chub up as a child (although you really never know, I guess).
Any thoughts on the two?
Oh, and the Marathon definitely was super plush. It seriously looked like a little baby LazyBoy.
I think if they made them for adults, I would love to ride in something like that in a car! DS will need all the extra seat height he can get though, unfortunately.